Here's a productive twist on the animated characters known as avatars that carry out fantasies in virtual computer worlds. IBM Corp. researchers have developed an avatar that can translate spoken words into sign language.

The technology is meant for use in the real world and could be useful when human interpreters for the deaf are unavailable, or when a conversation is sensitive. Imagine sitting through a lecture and seeing a digital character projected on a screen behind the speaker, interpreting the speech in real time.

The IBM team and advocates for the deaf caution that the system is still a prototype. It also works only with British Sign Language for now because it was created at an IBM research center in Hursley, England.

But the system, known as SiSi (for "Say It Sign It"), is expected to move out of the labs and into commercial products. It is designed to be baked into other vendors'...